package thread;

public class ThreadDemo1 {
    public static void main(String[] args) {
        Thread1 t1 = new Thread1();
        Thread2 t2 = new Thread2();
        t1.start();
        t2.start();
    }
}
class Thread1 extends Thread{
    public void run(){
        for (int i = 0;i<1000;i++){
            System.out.println("你是谁？");
        }
    }
}
class Thread2 extends Thread{
    public void run(){
        for (int i = 0;i<1000;i++){
            System.out.println("开门！");
        }
    }
}